General Description

The ICS9248-171 is a main clock synthesizer chip for AMD-K7 based systems with ALI 1647 style chipset. This provides all clocks required for such a system.

Features:

• Up to 147MHz frequency support

• Support power management: DG stop, PCI stop and Power down Mode from I2C programming.

• Spread spectrum for EMI control (0 to -0.5 down spread, ± 0.25 center spread).

• Uses external 14.318MHz crystal

Output Features:

• 1 - Differential pair open drain CPU clocks

• 1 - Single-ended open drain CPU clock

• 13 - SDRAM @ 3.3V

• 7 - PCI @3.3V

• 2 - AGP @ 3.3V

• 1 - 48MHz, @3.3V

• 1 - REF @3.3V, (selectable strength) through I2C